<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>栅格系统</title>
    <!--引入必须的资源文件-->
    <link rel="stylesheet" href="../css/bootstrap.css">
    <script type="text/javascript" src="../js/jquery-3.3.1.js"></script>
    <script type="text/javascript" src="../js/bootstrap.js"></script>
    <style>
        a{
            display: block;
            border: 1px solid deeppink;
        }
    </style>
</head>
<body>
    <div class="container-fluid">
        <div class="row">
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
            <a class="col-md-1">1</a>
        </div>
        <hr/>
        <div class="row">
            <a class="col-md-8">8</a>
            <a class="col-md-4">4</a>
        </div>
        <hr/>
        <div class="row">
            <a class="col-md-4">4</a>
            <a class="col-md-4">4</a>
            <a class="col-md-4">4</a>
        </div>
        <hr/>
        <div class="row">
            <a class="col-md-3 col-sm-6">3</a>
            <a class="col-md-3 col-sm-6">3</a>
            <a class="col-md-3 col-sm-6">3</a>
            <a class="col-md-3 col-sm-6">3</a>
        </div>
    </div>
</body>
</html>